1. Field of the Invention
The invention relates generally to a gas turbine, and, more specifically to an air-bleed gas turbine that includes air bleed means through which the compressed air, which is supplied from a compressor toward a combustor, is partially supplied to a device outside the gas turbine.
2. Description of the Related Art
An air-bleed gas turbine, which is one type of gas turbine, is in common use recently. The air-bleed gas turbine includes air bleed means, such as an air bleed port, an air bleed pipe, and an air bleed duct, through which the compressed air, supplied from a compressor toward a combustor, is partially supplied to a device outside the gas turbine.
Japanese Patent Application Publication No. 2000-356139 (JP-A-2000-356139) describes examples of the air-bleed gas turbine of the aforementioned type. FIG. 2 in JP-A-2000-356139 illustrates the configuration in which an air bleed port is communicated with a space in which a combustor that receives the compressed air from a compressor is housed. Further, FIG. 1 in JP-A-2000-356139 illustrates the configuration in which an air bleed port is communicated with a cavity that is separated from a space, in which the combustor is housed, by a partition. In this configuration, the compressed air is partially introduced through an air bleed hole formed in a diffuser of the compressor into the cavity which is communicated with the air bleed port.
In the air-bleed gas turbine configured as shown in FIG. 1 in JP-A-2000-356139, the compressed air from the compressor is supplied into the cavity through the air bleed hole formed in the diffuser, and then bled through the air bleed port from the cavity. This configuration makes it difficult to bleed a large amount of compressed air.
On the other hand, in the air-bleed gas turbine configured as shown in FIG. 2 in JP-A-2000-356139, a large amount of air may be bled through the air bleed port. However, with this configuration, there is a possibility that the pressure distribution of the compressed air that is supplied to the combustor is uneven because the pressure around the air bleed port decreases, resulting in unstable combustion in the combustor.